Sensor assembly and volatile organic compound detector

Abstract

The utility model discloses a sensor assembly for detecting the concentration of volatile organic compounds and a volatile organic compound detector. The sensor assembly comprises a body and a concentration sensor, a detection flow channel, a gas inlet channel and a gas outlet channel are formed in the body, the detection flow channel is connected between the gas inlet channel and the gas outlet channel, and gas flows into the detection flow channel from the gas inlet channel and then flows into the gas outlet channel through the detection flow channel; the concentration sensor is arranged on the body and provided with an induction opening, and the induction opening is exposed to one side of the detection flow channel. According to the invention, stable airflow can be obtained, turbulence influence is eliminated, a stable test result can be obtained, large fluctuation of a test value is avoided, the size and direction of the airflow passing through the induction port are easy to control, and the test precision is effectively improved. In addition, after the test is completed, the system can recover to a testable state more quickly.

Description

Technical Field

[0001] The present technology relates to the field of volatile organic compound detection, and in particular to a sensor assembly and a volatile organic compound detector for volatile organic compound concentration detection. Background Art

[0002] Theoretically, all chemical substances can be ionized, but the energy required for ionization is different. The energy required to ionize a compound is called "ionization potential" (IP), which is measured in electron volts (eV).

[0003] The energy emitted by an ultraviolet (UV) lamp is also measured in eV. If the "ionization potential" IP of the gas being measured is lower than the output energy of the lamp, the gas can be ionized and detected. Based on this principle, the photochemical ionization sensor (PID) ionizes different types of gases through the different output energies of the ultraviolet lamp (9.8eV, 10.6eV, 11.7eV3), so that the organic molecules in the gas are ionized into positive and negative ions (ionization) that can be detected by the detector. Afterwards, the PID sensor detector captures the positive and negative charges of the ionized gas and converts them into current or voltage signals to measure the gas concentration.

[0004] The gas concentration detection range of the PID sensor is generally a wide range from a few ppb (parts per billion) to tens of thousands of ppm (parts per million). When the sensor encounters the reaction gas, it outputs an electrical signal through photoelectric conversion, and the gas concentration value can be obtained through data analysis and processing.

[0005] An existing VOC (Volatile Organic Compounds) test scheme includes a cavity and a sensor. The cavity is formed with a cylindrical air chamber, which penetrates downward and matches the outer wall of the sensor, and the top wall of the cavity is provided with an air inlet, the side wall is provided with an air outlet, or one side of the cavity is provided with an air inlet, and the other side is provided with an air outlet. The sensor extends into the air chamber so that the sensing port of the sensor is exposed to the air chamber. This test scheme uses a pump (not shown) to suck the measured gas into the air chamber from the air inlet and discharge it from the air outlet. The sensor contacts the gas in the air chamber, thereby measuring the concentration of volatile organic compounds in the gas. This scheme has a fast response. However, since the air chamber matches the outer wall of the sensor, the sensing port is exposed in an air chamber that is much larger than its size, and turbulence is easily generated in the air chamber, resulting in unstable testing, large fluctuations in test values, and it is also difficult to control the size and direction of the airflow passing through the sensing port of the sensor, thereby affecting the test accuracy. Moreover, this test scheme also has the disadvantage of slow recovery after the test is completed.

[0006] Therefore, the existing testing scheme cannot meet the requirements of high precision and small fluctuation of VOC testing on the current production line, and can only be used in industries that detect the presence of high concentrations of VOC gases. Utility Model Content

[0007] The present application aims to provide a sensor assembly and a volatile organic compound detector for detecting volatile organic compound concentration, which can solve the technical problems of large test value fluctuations, poor test accuracy and slow test recovery existing in the existing VOC detectors in the above-mentioned background technology.

[0008] To achieve the above-mentioned purpose, the present application provides a sensor assembly for detecting the concentration of volatile organic compounds, including a body and a concentration sensor;

[0009] The main body is formed with a detection channel, an air inlet channel and an air outlet channel, the detection channel is connected between the air inlet channel and the air outlet channel, the gas flows from the air inlet channel into the detection channel, and then flows into the air outlet channel through the detection channel;

[0010] The concentration sensor is arranged on the body and has a sensing port. The sensing port is arranged corresponding to a position of the detection flow channel on the flow path and is exposed on one side of the detection flow channel.

[0011] Optionally, the body includes a first body and a second body that are relatively fixed;

[0012] The detection flow channel and the air inlet channel are arranged on the first body, wherein the detection flow channel is opened on the lower surface of the first body;

[0013] The second body is provided with the air outlet channel and a mounting opening penetrating from top to bottom;

[0014] The first body is disposed on the second body by fitting the lower surface thereof, and the detection flow channel is at least partially exposed at the installation opening;

[0015] The concentration sensor is adapted to be arranged at the installation opening, and the end surface of the concentration sensor is attached to the lower surface of the first body to seal the detection flow channel.

[0016] Optionally, a first ring portion protrudes upward from the periphery of the second body, and the first ring portion is adapted to be fitted on the outer side surface of the first body.

[0017] Optionally, the air inlet channel includes a first air inlet hole and a second air inlet hole, the first air inlet hole is opened in the middle of the upper surface of the first body, and the second air inlet hole connects the bottom of the first air inlet hole and one end of the detection channel.

[0018] Optionally, the sensor assembly also includes a cover body, which includes a top plate and a second ring portion extending downward from the periphery of the top plate, the top plate is crimped on the first body, and the second ring portion is sleeved on the outer side surface of the first ring portion; a first boss extends downward from the middle portion of the top plate, a through hole is formed on the first boss extending upward and downward, the first boss is inserted into the first air inlet hole, and the through hole is connected to the second air inlet hole.

[0019] Optionally, the sensor assembly further comprises a filter having an air inlet and an air outlet, wherein the air outlet is connected to the through hole of the cover body via a joint.

[0020] Optionally, the sensor assembly further includes a base, the base is configured to be fixedly mounted on the detector body, the second body is fixedly disposed on the base, a mounting groove is provided on the base, and the concentration sensor is mounted in the mounting groove.

[0021] Optionally, an air outlet is formed on the base, one end of the air outlet is communicated with the air outlet channel, and the other end of the air outlet is connected to the adapter.

[0022] Optionally, the upper surface of the base is provided with a plurality of first mounting holes, the second body is provided with a plurality of second mounting holes that pass through the base from top to bottom and correspond to the plurality of first mounting holes respectively, the first body is provided with a plurality of avoidance holes that correspond to the plurality of second mounting holes respectively, and the second body and the base are fixedly connected by the cooperation of a plurality of fasteners with the plurality of first mounting holes and the plurality of second mounting holes, and the heads of the plurality of fasteners are respectively placed in the plurality of avoidance holes to position the first body.

[0023] To achieve the above-mentioned objectives, the present application provides a volatile organic compound detector, including a detector body and the above-mentioned sensor assembly, the detector body including an air suction pump and a processing module, the sensor assembly being assembled on the detector body, the air outlet channel being connected to the air suction pump, and the concentration sensor being signal-connected to the processing module.

[0024] The present application forms a detection channel on the body of the sensor assembly, and sets the sensing port of the concentration sensor at a position on the flow path of the detection channel corresponding to the detection channel and exposed on one side of the detection channel. When the gas passes through the detection channel, the concentration sensor detects the volatile organic concentration of the gas in real time. Since the present application uses the detection channel to replace the traditional air chamber, and sets the sensing port of the concentration sensor at a position on the flow path of the detection channel corresponding to the detection channel and exposed on one side of the detection channel, when the gas enters from one end of the detection channel and flows out from the other end, a stable airflow can be obtained, eliminating the influence of turbulence, and thus a stable test result can be obtained, avoiding large fluctuations in the test value. Moreover, compared with the traditional air chamber, the detection channel is easy to control the size and direction of the airflow passing through the sensing port, thereby effectively improving the test accuracy. In addition, since the present application uses the detection channel to replace the traditional air chamber, it can be restored to a testable state more quickly after the test is completed. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the three-dimensional structure of the body and concentration sensor of the embodiment of the present application.

[0026] Figure 2 This is a schematic diagram of the exploded structure of the body and concentration sensor of the embodiment of the present application.

[0027] Figure 3 This is another schematic diagram of the decomposed structure of the body and concentration sensor of the embodiment of the present application.

[0028] Figure 4 It is a schematic diagram of the three-dimensional structure of the first body of the embodiment of the present application.

[0029] Figure 5 For this application Figure 4 Section view along line AA.

[0030] Figure 6 This is a front view of the first body of the embodiment of the present application.

[0031] Figure 7 It is a schematic diagram of the three-dimensional structure of the sensor assembly according to an embodiment of the present application.

[0032] Figure 8 This is a schematic diagram of the exploded structure of the sensor assembly according to an embodiment of the present application.

[0033] Fig. 9 for Figure 7 Cross-sectional view along line BB.

[0034] Fig.10 It is a schematic diagram of the three-dimensional structure of the concentration sensor, base and adapter according to the embodiment of the present application.

[0035] Fig.11 for Fig.10 Sectional view along the CC line.

[0036] Fig.12 It is a schematic diagram of the decomposition structure of an embodiment of the present application.

[0037] Fig.13 It is a schematic diagram of a volatile organic compound detector according to an embodiment of the present application. DETAILED DESCRIPTION

[0038] In order to explain the technical content, structural features, achieved objectives and effects of the present application in detail, the following is a detailed description in conjunction with the implementation methods and the accompanying drawings.

[0039] See also Figures 1 to 3 The present application discloses a sensor assembly for detecting the concentration of volatile organic compounds, including a body 1 and a concentration sensor 2.

[0040] The main body 1 is formed with a detection channel 11, an air inlet channel 12 and an air outlet channel 13. The detection channel 11 is connected between the air inlet channel 12 and the air outlet channel 13. The gas flows from the air inlet channel 12 to the detection channel 11, and then flows into the air outlet channel 13 through the detection channel 11. The concentration sensor 2 is arranged on the main body 1, and the concentration sensor 2 has a sensing port 21. The sensing port 21 is arranged at a position corresponding to the detection channel 11 on the flow path and is exposed on one side of the detection channel 11.

[0041] In some embodiments, the body 1 includes a relatively fixed first body 14 and a second body 15. The detection channel 11 and the air inlet channel 12 are arranged in the first body 14, wherein the detection channel 11 is opened on the lower surface of the first body 14. The second body 15 is provided with an air outlet channel 13 and an installation port 151 that runs through the upper and lower parts. The first body 14 is fitted on the second body 15 through its lower surface, and the detection channel 11 is at least partially exposed at the installation port 151. The concentration sensor 2 is adapted to be arranged at the installation port 151, and the end face of the concentration sensor 2 is fitted on the lower surface of the first body 14 to seal the detection channel 11.

[0042] Specifically, when the gas passes through the sensing port 21 , the concentration sensor 2 ionizes the volatile organic matter in the gas and detects the concentration of the ionized volatile organic matter ions.

[0043] Specifically, a first ring portion 152 protrudes upward from the periphery of the second body 15 , and the first ring portion 152 is adapted to be fitted on the outer side surface of the first body 14 , thereby limiting the position of the first body 14 .

[0044] See also Figure 4 and Figure 5 Specifically, the air inlet channel 12 includes a first air inlet hole 121 and a second air inlet hole 122 . The first air inlet hole 121 is opened in the middle of the upper surface of the first body 14 . The second air inlet hole 122 connects the bottom of the first air inlet hole 121 and one end of the detection channel 11 .

[0045] See also Figure 4 and Figure 6 In some embodiments, the detection flow channel 11 includes a gradually expanding portion 111, a bottleneck portion 112 and an outlet portion 113 connected end to end. The starting end of the gradually expanding portion 111 is connected to the air inlet channel 12, and the gradually expanding portion 111 gradually widens from the starting end to the end connected to the bottleneck portion 112, and the outlet portion 113 is connected to the air outlet channel 13. The sensing port 21 corresponds to the end of the gradually expanding portion 111 close to the bottleneck portion 112.

[0046] Optionally, the first body 14 and the second body 15 may be fixedly connected by using positioning holes and fasteners.

[0047] See also Figures 7 to 9 Specifically, the sensor assembly also includes a cover body 3, which includes a top plate 31 and a second ring portion 32 extending downward from the periphery of the top plate 31, the top plate 31 is crimped on the first body 14, and the second ring portion 32 is sleeved on the outer side of the first ring portion 152; a first boss 33 extends downward from the middle of the top plate 31, and a through hole 34 is formed on the first boss 33 that penetrates from top to bottom, the first boss 33 is inserted into the first air inlet hole 121, and the through hole 34 is connected to the second air inlet hole 122.

[0048] Specifically, the sensor assembly further includes a filter 4, the filter 4 having an air inlet 41 and an air outlet 42, the air outlet 42 being connected to the through hole 34 of the cover body 3 via a joint 43. More specifically, a second boss 35 is formed on the upper surface of the cover body 3, the through hole 34 passes through the second boss 35 upward, one end of the joint 43 is sleeved on the outside of the air outlet 42 of the filter 4, and the other end is inserted into the through hole 34 and abuts against the second boss 35.

[0049] Optionally, the filter 4 extends upward to form a protrusion 44, and the lower part of the protrusion 44 extends outward to form a first step 45. When the filter 4 needs to be inserted into the object to be detected, the first step 45 can be abutted against the outer surface of the object to be detected to prevent the sensor assembly from being too close to the object to be detected.

[0050] See also Figures 7 to 13Specifically, the sensor assembly also includes a base 5, which is configured to be fixedly mounted on the detector body 7, the second body 15 is fixedly disposed on the base 5, a mounting groove 52 is provided on the base 5, and the concentration sensor 2 is mounted in the mounting groove 52.

[0051] Specifically, the upper surface of the base 5 is provided with a plurality of first mounting holes 57, the second body 15 is provided with a plurality of second mounting holes 154 which pass through from top to bottom and correspond to the plurality of first mounting holes 57 respectively, the first body 14 is provided with a plurality of avoidance holes 141 which correspond to the plurality of second mounting holes 154 respectively, the second body 15 and the base 5 are fixedly connected by a plurality of fasteners (such as screws, not shown) cooperating with the plurality of first mounting holes 57 and the plurality of second mounting holes 154, the heads of the plurality of fasteners are respectively placed in the plurality of avoidance holes 141 and the first body 14 is positioned, so that while the second body 15 and the base 5 are fixedly connected by the fasteners, the first body 14 can also be positioned by the fasteners.

[0052] Specifically, the second body 15 extends downwardly out of a third ring portion 153 , and the third ring portion 153 is adaptably connected to the base 5 , thereby limiting the position of the second body 15 .

[0053] Specifically, an air outlet 51 is formed on the base 5 of the sensor assembly, one end of the air outlet 51 is connected to the air outlet channel 13 , and the other end of the air outlet 51 is connected to the adapter 6 . More specifically, the adapter 6 is plugged into the other end of the air outlet 51 .

[0054] See also Figures 10 to 12 Further, the sensor assembly further includes a sensor circuit board 22 and a fixing plate 23, wherein the sensor circuit board 22 is fixedly mounted on the fixing plate 23. The mounting groove 52 passes through the base 5 from top to bottom, and a second step 53 is provided at one end of the mounting groove 52 close to the lower surface of the base 5, the concentration sensor 2 is inserted into the mounting groove 52 from the upper end thereof and supported on the second step 53, the sensor circuit board 22 and the fixing plate 23 are assembled to the mounting groove 52 from the lower side of the mounting groove 52 and supported on the second step 53, wherein the sensor circuit board 22 faces the concentration sensor 2.

[0055] Furthermore, a positioning groove 54 is formed on the side wall of the mounting groove 52 located at the lower side of the second step 53, and a positioning protrusion 222 is extended outward on one side of the sensor circuit board 22. When the sensor circuit board 22 and the fixing plate 23 are assembled together in the mounting groove 52, the positioning protrusion 222 is inserted into the positioning groove 54 for positioning the sensor circuit board 22 and the fixing plate 23, thereby facilitating the rapid assembly of the sensor circuit board 22 and the fixing plate 23.

[0056] Optionally, a retaining ring installation groove 58 is formed at one end of the side wall of the installation groove 52 close to the lower surface of the base 5. After the sensor circuit board 22 and the fixing plate 23 are assembled, a retaining ring (not shown) is installed from the lower opening of the installation groove 52 to the retaining ring installation groove 58 to fix the sensor circuit board 22 and the fixing plate 23.

[0057] The present application forms a detection channel 11 on the body 1 of the sensor assembly, and sets the sensing port 21 of the concentration sensor 2 at a position on the flow path of the detection channel 11 corresponding to the detection channel 11 and is exposed on one side of the detection channel 11. When the gas passes through the detection channel 11, the concentration sensor 2 detects the volatile organic concentration of the gas in real time. Since the present application uses the detection channel 11 to replace the traditional air chamber, and sets the sensing port 21 of the concentration sensor 2 at a position on the flow path of the detection channel 11 corresponding to the detection channel 11 and is exposed on one side of the detection channel 11, when the gas enters from one end of the detection channel 11 and flows out from the other end, a stable airflow can be obtained, eliminating the influence of turbulence, and thus a stable test result can be obtained, avoiding large fluctuations in the test value, and the detection channel 11 is easier to control the size and direction of the airflow passing through the sensing port 21 than the traditional air chamber, thereby effectively improving the test accuracy. In addition, since the present application uses the detection channel 11 to replace the traditional air chamber, it can be restored to a testable state more quickly after the test is completed.

[0058] See also Figure 7 and Fig.13 The present application also discloses a volatile organic compound detector, including a detector body 7 and the above-mentioned sensor assembly, the detector body 7 includes an air suction pump 8 and a processing module 9, the sensor assembly is assembled on the detector body 7, the air outlet channel 13 is connected to the air suction pump 8, and the concentration sensor 2 is signal-connected to the processing module 9.

[0059] In some embodiments, the air pump 8 is connected to the adapter 6 installed at the bottom of the base 5 through a pipe 81. When performing volatile organic compound concentration detection, the air pump 8 sucks external gas into the sensor assembly. After being filtered by the filter 4, the gas flows from the air inlet channel 12 of the body 1 into the detection flow channel 11, and then flows out from the air outlet channel 13 to the air outlet hole 51 on the base 5, and then flows into the pipe 81 through the adapter 6. The pipe 81 between the air pump 8 and the adapter 6 can be a rubber pipe or a plastic pipe, etc., without specific limitation.

[0060] In some embodiments, the bottom of the base 5 is formed with a flange 55 protruding outward, and the detector body 7 is provided with a stopper 71. When the base 5 passes through the stopper 71, the flange 55 stops the base 5 on the stopper 71. The flange 55 is provided with a plurality of through holes 56, and the base 5 can be fixed on the stopper 71 by screws or the like.

[0061] The above disclosure is only a preferred example of the present application and cannot be used to limit the scope of rights of the present application. Therefore, equivalent changes made according to the claims of the present application are all within the scope covered by the present application.

Claims

1. A sensor assembly for detecting the concentration of volatile organic compounds, characterized in that: It includes a main body and a concentration sensor; The main body is formed with a detection channel, an air inlet channel and an air outlet channel, the detection channel is connected between the air inlet channel and the air outlet channel, the gas flows from the air inlet channel into the detection channel, and then flows into the air outlet channel through the detection channel; The concentration sensor is arranged on the body and has a sensing port. The sensing port is arranged corresponding to a position of the detection flow channel on the flow path and is exposed on one side of the detection flow channel.

2. The sensor assembly according to claim 1, characterized in that The body comprises a first body and a second body which are relatively fixed; The detection flow channel and the air inlet channel are arranged on the first body, wherein the detection flow channel is opened on the lower surface of the first body; The second body is provided with the air outlet channel and a mounting opening penetrating from top to bottom; The first body is disposed on the second body by fitting the lower surface thereof, and the detection flow channel is at least partially exposed at the installation opening; The concentration sensor is adapted to be arranged at the installation opening, and the end surface of the concentration sensor is attached to the lower surface of the first body to seal the detection flow channel.

3. The sensor assembly according to claim 2, characterized in that A first ring portion protrudes upward from the periphery of the second body, and the first ring portion is adapted to be fitted on the outer side surface of the first body.

4. The sensor assembly according to claim 3, characterized in that The air inlet channel includes a first air inlet hole and a second air inlet hole, wherein the first air inlet hole is opened in the middle of the upper surface of the first body, and the second air inlet hole communicates with the bottom of the first air inlet hole and one end of the detection channel.

5. The sensor assembly according to claim 4, characterized in that It also includes a cover body, which includes a top plate and a second ring portion extending downward from the periphery of the top plate, the top plate is crimped on the first body, and the second ring portion is sleeved on the outer side surface of the first ring portion; a first boss extends downward from the middle part of the top plate, a through hole is formed on the first boss extending upward and downward, the first boss is inserted into the first air inlet hole, and the through hole is connected to the second air inlet hole.

6. The sensor assembly according to claim 5, characterized in that It also includes a filter, which has an air inlet and an air outlet, and the air outlet is connected to the through hole of the cover body through a joint.

7. The sensor assembly according to claim 2, characterized in that It also includes a base, which is configured to be fixedly installed on the detector body, the second body is fixedly arranged on the base, the base is provided with a mounting groove, and the concentration sensor is installed in the mounting groove.

8. The sensor assembly according to claim 7, characterized in that An air outlet is formed on the base, one end of the air outlet is communicated with the air outlet channel, and the other end of the air outlet is connected to the adapter.

9. The sensor assembly according to claim 7, characterized in that The upper surface of the base is provided with a plurality of first mounting holes, the second body is provided with a plurality of second mounting holes which pass through the upper and lower parts respectively corresponding to the plurality of first mounting holes, the first body is provided with a plurality of avoidance holes which correspond to the plurality of second mounting holes respectively, the second body and the base are fixedly connected by the cooperation of a plurality of fasteners with the plurality of first mounting holes and the plurality of second mounting holes, the heads of the plurality of fasteners are respectively placed in the plurality of avoidance holes to position the first body.

10. A volatile organic compound detector, characterized in that: It comprises a detector body and a sensor assembly as described in any one of claims 1 to 9, wherein the detector body comprises an air suction pump and a processing module, the sensor assembly is assembled on the detector body, the air outlet channel is connected to the air suction pump, and the concentration sensor is signal-connected to the processing module.

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